Clarify proxy documentation
Clarify proxy documentation

- note that the port changes on every deploy when the proxy is disabled
- make it clear that the proxy is being disabled for the app
- note that the nginx-vhosts plugin supports the proxy plugin mapping
- minor formatting changes

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sseemayer/dokku,fruitl00p/dokku,alexquick/dokku,progrium/dokku,Evlos/dokku,fruitl00p/dokku,amaltson/dokku,sseemayer/dokku,econya/dokku,johnfraney/dokku,alexquick/dokku,claytonbrown/dokku,claytonbrown/dokku,progrium/dokku,Evlos/dokku,fruitl00p/dokku,sseemayer/dokku,expa/dokku,econya/dokku,econya/dokku,dokku/dokku,alexquick/dokku,amaltson/dokku,sseemayer/dokku,expa/dokku,progrium/dokku,econya/dokku,amaltson/dokku,Evlos/dokku,sseemayer/dokku,elia/dokku,Evlos/dokku,amaltson/dokku,johnfraney/dokku,claytonbrown/dokku,progrium/dokku,johnfraney/dokku,alexquick/dokku,econya/dokku,progrium/dokku,dokku/dokku,sseemayer/dokku,alexquick/dokku,claytonbrown/dokku,sseemayer/dokku,expa/dokku,elia/dokku,expa/dokku,dokku/dokku,sseemayer/dokku,johnfraney/dokku,jimjag/dokku,fruitl00p/dokku,elia/dokku,Evlos/dokku,dokku/dokku,claytonbrown/dokku,johnfraney/dokku,fruitl00p/dokku,jimjag/dokku,jimjag/dokku,dokku/dokku,expa/dokku,claytonbrown/dokku,dokku/dokku,alexquick/dokku,progrium/dokku,jimjag/dokku,jimjag/dokku,elia/dokku,Evlos/dokku,jimjag/dokku,amaltson/dokku,fruitl00p/dokku,progrium/dokku,Evlos/dokku,econya/dokku,fruitl00p/dokku,elia/dokku,Evlos/dokku,johnfraney/dokku,econya/dokku,progrium/dokku,fruitl00p/dokku,johnfraney/dokku,elia/dokku,amaltson/dokku,expa/dokku,claytonbrown/dokku,claytonbrown/dokku,dokku/dokku,elia/dokku,alexquick/dokku,expa/dokku,dokku/dokku,elia/dokku,amaltson/dokku,amaltson/dokku,econya/dokku,johnfraney/dokku,expa/dokku,jimjag/dokku,alexquick/dokku,jimjag/dokku